This invention relates to a process for forming an ultrafine-particle film, particularly to a process for forming an ultrafine-particle film in which various compounds, irrespective of metal or nonmetal, can be used as ultrafine particle materials.
For producing ultrafine particles by means of an arc, there has heretofore been utilized a mechanism in which a hydrogen-containing gas is dissolved in a molten metal, subjected to convection current therein, and liberated therefrom, as disclosed, for example, in U.S. Pat. No. 4,482,134 and Japanese Patent Publication No. 44725/82.
As methods for forming the thus obtained ultrafine particles into a film, there are known a method comprising coating a solution prepared by dissolving the particles in a solvent, and a method comprising spraying the particles by utilizing a gas flow.
In the above conventional production of ultrafine particles, the production efficiency is not taken into consideration. The conventional film forming methods described above have their respective defects as follows: the former method hardly permits formation of a film of high purity, while the latter method requires a complicated apparatus.